17 research outputs found
Plain language summary of publication: Neurexan reduced blood stress biomarkers in sled dogs after exercise
This is a plain language summary of a published peer-reviewed article in English, German, Spanish and Russian. It refers to a veterinary study investigating impact of training-induced stress response in sled dogs during high intensity training. This summary was not peer-reviewed but it represents the opinions of the authors. For a full list of declarations, including funding and author disclosure statements, please read the full open-access article online.</p
Uneven distribution of enamel, dentine and cementum in cheek teeth of domestic horses (<i>Equus caballus</i>): A micro computed tomography study
<div><p>Background</p><p>Hypsodont equine cheek teeth possess large dental crowns, resting partly in the bony alveolus. Over a horse’s life cheek teeth erupt continuously to compensate for occlusal wear of 3–4 mm per year. Parts of the crown initially resting in the bony alveolus become progressively exposed at the occlusal surface with time. Hitherto, it is unclear whether the typical structure of the equine occlusal surface, composed of a complex arrangement of enamel, dentin and cementum, remains constant or undergoes structural changes with age. Therefore, we tested the hypothesis that the occlusal surface composition does not remain constant by a quantitative analysis of the dental substances at multiple levels along the dental crown of equine cheek teeth.</p><p>Methods</p><p>Micro-computed tomography scans of 20 upper cheek teeth and 16 lower cheek teeth from 19 domestic horses were morphologically analysed using imaging and measurement software. Area for individual dental substances was measured at different levels from the apex to the occlusal surface. The data was statistically analysed to detect changes in the area of individual substance along the dental crown. The area of peripheral cementum was measured separately for levels inside and outside the bony alveolus.</p><p>Results</p><p>In both, upper and lower cheek teeth, enamel area decreased in an apical direction, while dentine area increased. Peripheral Cementum increased dramatically in the occlusal/coronal extra-alveolar position.</p><p>Conclusion</p><p>With increasing age the occlusal surface content of dentine increases while the content of enamel decreases. These changes are considered relevant for the detailed explanation of forage disruption in horses as well as for the recommendation of concepts in equine dentistry.</p></div
Upper and lower cheek teeth used in this study.
<p>Upper and lower cheek teeth used in this study.</p
Boxplots representing the absolute area of tooth substances (dentine + enamel) and the absolute area of tooth substances plus peripheral cementum for UCT and LCT.
<p>The boxes represent the interquartile range (25%, 75%), the horizontal line the median and the whiskers the range.</p
Results of the intra-class correlation analysis for the slopes concerning LCT.
<p>Results of the intra-class correlation analysis for the slopes concerning LCT.</p
Boxplots representing the area of peripheral cementum in intra-alveolar and extra-alveolar position for LCT and UCT.
<p>The boxes represent the interquartile range (25%, 75%), the horizontal line the median and the whiskers the range.</p
MicroCT images of a 109.
<p>(A)MicroCT image of a 109, longitudinal section. Depending on the tooth height up to nine equal spaced (10 mm) horizontal sections presenting a complete layer of peripheral enamel were selected for measurements. Additionally the most occlusal section (mo) of the crown showing a complete layer of peripheral enamel was selected. (B,D) MicroCT cross section showing the typical arrangement of the dental substances of an upper (B) and lower (D) cheek tooth. (C,E) MicroCt cross section as in B,D with selected enamel (yellow), dentine (light red) and cementum (blue) to define areas for measurement.</p
MicroCT of an UCT, longitudinal section.
<p>Bars indicating decrease / increase of dental substances along the dental crown. P values < 0.05 are marked with *. (A) Calculated mean absolute changes per 10 mm crown height. (B) Calculated mean relative changes per 10 mm crown height.</p
Volume determination based on MRI-datasets.
<p>Image segmentation of white matter and grey matter using manual segmentation on a slice-by-slice basis from transverse images. Each tissue of interest is labelled red and thereby assigned to a group (mask). All masks are then assembled and the tissues can be depicted in volume form.</p
Linear regression model analysis of the changes in relative grey matter (GM), white matter (WM)- and CSF volume and the WM/GMratio with increasing bodyweight in dogs.
<p>The relative grey matter (GM), white matter (WM), and CSF volume of the lateral venmtricles as well as the WM/GM-ratio is plotted against the bodyweight in two groups of dogs. The open circles represent dogs with subjectively normal ventricles, the filled circles represent dogs with enlarged ventricles. The adjusted means in the middle of the regression lines of the groups differs significantly.</p